TY - JOUR
T1 - Synthesis and Characterization of 1,1′-Diphosphaplumbocenes
T2 - Oxidative Ligand Transfer Reactions with Divalent Thulium Complexes
AU - Jaroschik, Florian
AU - Momin, Aurélien
AU - Martinez, Agathe
AU - Harakat, Dominique
AU - Ricard, Louis
AU - Le Goff, Xavier Frédéric
AU - Nocton, Grégory
N1 - Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/6/13
Y1 - 2016/6/13
N2 - The new 1,1′-diphosphaplumbocenes Pb(Dtp)2 (Dtp = 2,5-di-tert-butyl-3,4-dimethylphospholyl) and Pb(Dsp)2 (Dsp = 2,5-ditrimethylsilyl-3,4-dimethylphospholyl) have been synthesized and characterized by multinuclear NMR spectroscopy. 207Pb NMR spectra of both complexes, as well as for the known complex Pb(Htp)2 (Htp = 2,5-di-tert-butylphospholyl), show that the phospholyl ligands lead to an important downfield shift compared with that of cyclopentadienyl based plumbocenes. X-ray diffraction studies of the Pb(Dtp)2 complex revealed a structure with two slightly bent η5-bound ligands. This complex was employed in the oxidative ligand transfer reaction with bulky divalent thulium complexes. In the case of Tm(Dtp)2, the first example of a monomeric trivalent tris(phospholyl)lanthanide complex Tm(Dtp)3 was obtained. X-ray diffraction studies and low-temperature 1H NMR studies show the η1 coordination mode of the third Dtp ligand. In contrast, oxidation of Tm(Cpttt)2 (Cpttt is for tris-tert-butylcyclopentadienyl) led presumably to the formation of the ion pair complex [Tm(Cpttt)2][Dtp], in which no interaction between the free Dtp ligand and Tm was observed, as shown by variable temperature 1H and 31P NMR studies. The new trivalent complexes could be reduced back to the original divalent complexes with potassium graphite.
AB - The new 1,1′-diphosphaplumbocenes Pb(Dtp)2 (Dtp = 2,5-di-tert-butyl-3,4-dimethylphospholyl) and Pb(Dsp)2 (Dsp = 2,5-ditrimethylsilyl-3,4-dimethylphospholyl) have been synthesized and characterized by multinuclear NMR spectroscopy. 207Pb NMR spectra of both complexes, as well as for the known complex Pb(Htp)2 (Htp = 2,5-di-tert-butylphospholyl), show that the phospholyl ligands lead to an important downfield shift compared with that of cyclopentadienyl based plumbocenes. X-ray diffraction studies of the Pb(Dtp)2 complex revealed a structure with two slightly bent η5-bound ligands. This complex was employed in the oxidative ligand transfer reaction with bulky divalent thulium complexes. In the case of Tm(Dtp)2, the first example of a monomeric trivalent tris(phospholyl)lanthanide complex Tm(Dtp)3 was obtained. X-ray diffraction studies and low-temperature 1H NMR studies show the η1 coordination mode of the third Dtp ligand. In contrast, oxidation of Tm(Cpttt)2 (Cpttt is for tris-tert-butylcyclopentadienyl) led presumably to the formation of the ion pair complex [Tm(Cpttt)2][Dtp], in which no interaction between the free Dtp ligand and Tm was observed, as shown by variable temperature 1H and 31P NMR studies. The new trivalent complexes could be reduced back to the original divalent complexes with potassium graphite.
U2 - 10.1021/acs.organomet.6b00313
DO - 10.1021/acs.organomet.6b00313
M3 - Article
AN - SCOPUS:84974737259
SN - 0276-7333
VL - 35
SP - 2032
EP - 2038
JO - Organometallics
JF - Organometallics
IS - 11
ER -